This invention relates to focusing a stereoscopic optical system. The invention also relates to rangefinding and videometry in an imaging system.
Stereoscopic optical systems are used in a variety of applications. One environment in which stereoscopic (i.e., three-dimensional) viewing has become useful is the field of endoscopic surgery. During this type of surgery, an endoscope is inserted into the body through a small puncture opening to allow the user to visualize the surgical site without fully opening the wound. The endoscope supplies light to the surgical site through a set of optical fibers that extend along the length of the endoscope. An image pickup device (such as a solid-state sensor, e.g., a charge-coupled device or CCD) receives optical images of objects in the surgical site from an optical assembly, and converts the images to electrical signals for visualization on an electronic display. The image pickup device can be located at the distal tip of the endoscope, in the proximal, handle end of the endoscope, or anywhere in between.
Stereoscopic optical systems produce a video image of an object by acquiring separate left and right images of the object from two different viewing angles. The systems display the right image to the observer's right eye, and separately display the left image to the observer's left eye to provide a three-dimensional view of the object.